Two-component tissue adhesives which are based on the reaction of fibrinogen with thrombin to form a fibrin clot are, when used on large areas, normally sprayed in order to obtain uniform thin fibrin films. An apparatus in which the administration syringes filled with the components are attached to a spray head is known (EP-A-0,302,411, subsequently referred to as (1)) for this purpose. This spray head has two separate channels for the two components and has a connector, equipped with a Luer Lock, for compressed air, whereby the components can be sprayed by the two syringe pistons being simply pushed forward simultaneously. Despite the good spraying results which can be achieved with this system, the latter is associated with considerable disadvantages on use which have prevented wider application:
it requires a compressed air or propellant gas connection which is present as a standard in most operating theaters in Germany. However, the standards outside Germany are different and incompatible, or the connections are completely absent; PA1 it requires a pressure reducer or controller in order to reduce the high pressure of a central compressed air supply to-an operating pressure of about 1.5 to 2.5 bar PA1 the compressed air emerging from the compressed air connection is by its nature non-sterile and must therefore be sterilized by filtration using a special filter; PA1 the connecting tubing between wall connection and the spray system must be long enough to allow use anywhere. For this reason, they normally tend to be supplied too long so that they can be regarded as traps to trip the operating staff. PA1 atomization outside the range of the pressure tubing is impossible, which means that the system cannot be used in an ambulance, on outpatients or by non-hospital physicians; and PA1 assembly of this system is time-consuming and provides various sources of error which may in hospital routine prove to be disturbing and even dangerous.
An apparatus similar to that in (1) is also described in EP-A-0,037,393 (2).